college Algebra
posted by Brianna on .
Let g(x) = 2x2 + bx + c be a quadratic function, defined everywhere, where b and c are constants. If x = 1 marks the location of one of the zeros of this quadratic function, and if the yintercept of this function is at (0, 5), then use this information to name constant b.

g = 2x^2 + bx + c
g = (x1)(2x + b2) remainder b+c2
In order for 1 to be a root, then x1 must divide g exactly. That is,
b+c2 = 0
Using the yintercept, when x=0, y=5
5 = c
So, b+3 = 0, or b=3
g = 2x^2 3x + 5 = (x1)(2x  5)